Field of the Invention
The present invention, generally relates to field of touch technologies, and more particularly to a touch technology for touch panels.
Description of Related Art
Nowadays, personal digital assistants (FDA), mobile phones, notebook computers, tablet PCs and other portable electronic products are being widely used in modern life. Since these electronic products need to be thinner and lighter in weight, the traditional input devices, such as keyboards or a mouse, have to be replaced with other input devices. In addition, as the need for tablet PCs has greatly increased, the touch panel technology has become one of the key components in the manufacturing of electronic products. Furthermore, since electronic products with light, thin and short forms have become a mainstream development trend, allowed space in these new-developed electronic products is no longer enough to accommodate conventional input devices such as key boards or mice.
Generally, a conventional touch panel includes an active region and a peripheral region having an opaque shelter layer surrounding the active region. In some products, a function key module is configured within the peripheral region and a portion of the corresponding shelter layer is etched away to form corresponding key icons. Since light emitting diodes (LED) are usually disposed under the shelter layer and corresponding to the key icons, light beams from the LEDs are emitted on the key icons so that a viewer is able to see the vivid key icons. The shelter layer, however, is often fabricated through printing or coating processes. Due to technical limitations in printing or coating processes, drawbacks such as uneven coating of the shelter layer or small bubbles within the shelter layer often, occur unavoidably, which thereby incurs pinholes formed in the shelter layer. In a normal condition, these pinholes are hardly visible to a viewer, but in a case when light beams from the LEDs are emitted on the shelter layer close to the key icons, the light beams will be transmitted through these pinholes and let these pinholes be visible to the viewer thereby inducing negative effects in the product's appearance.